@incollection{lee-2001,
  title     = {Algorithms for non-negative matrix factorization},
  author    = {Daniel D. Lee and Seung, H. Sebastian},
  booktitle = {Advances in Neural Information Processing Systems 13},
  pages     = {556--562},
  year      = 2001}

@article{blei-2003,
  author  = {David M. Blei and Andrew Y. Ng and Michael I. Jordan},
  title   = "Latent {Dirichlet} allocation",
  year    = {2003},
  journal = "Journal of Machine Learning Research",
  volume  = 3,
  pages   = {993--1022}}

@article{kim-2019,
  author  = {Youngseok Kim and Peter Carbonetto and Matthew Stephens and
             Mihai Anitescu},
  title   =  {A fast algorithm for maximum likelihood estimation of
              mixture proportions using sequential quadratic
              programming},
  journal = {arXiv},
  volume  = {1806.01412},
  year    = 2019,
  eprint  = {1806.01412},
  archivePrefix = "arXiv"}

